The importance of sustainable energy resources continues to rise along with worldwide energy demands. Solid-state thermoelectric modules have recently seen an increase in interest due to their ability to convert heat energy into electricity and such materials are desirable to harvest the vast amounts of waste heat produced by combustion-based energy generators.
The efficiency of energy conversion for a solid-state thermoelectric module depends on the dimensionless thermoelectric figure of merit ZT. It is known that the figure of merit can be described by the expression ZT=σS2/κT, where σ is the electrical conductivity; S is the thermoelectric power, also known as the Seebeck coefficient; K is the thermal conductivity; and T is the absolute temperature. Although σ, S and κ are interdependent in bulk materials and a ZT of greater than 1 is known to be difficult to achieve, theoretical studies of nanostructured materials suggest that these parameters can be tuned separately in low-dimensional systems. As such, a process for separately tuning, altering or changing σ, S and/or κ for a solid-state thermoelectric module would be desirable.